1
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Kim DK, Lee J, Lee DJ, Yun GS. Development of a toroidally resolved broadband ECE imaging system for measurement of turbulent fluctuations on the KSTAR. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:083507. [PMID: 39093114 DOI: 10.1063/5.0219245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Accepted: 07/17/2024] [Indexed: 08/04/2024]
Abstract
The two electron cyclotron emission imaging (ECEI) systems installed at adjacent ports (G and H) on the KSTAR tokamak incorporate large-aperture mm-wave optics, broadband electronics, and high speed digitization (up to 1 MSa/s) for 2D and quasi-3D visualization of MHD-scale fluid dynamics. Recently, the ECEI systems have been proved to be capable of visualization of smaller scale fluctuations albeit with a limited spatiotemporal resolution and even capable of measurement of ion cyclotron harmonic waves by direct high-speed sampling of the ECE IF signals. A four-channel prototype subsystem with a higher sampling rate up to 16 GS/s has been integrated into the G-port ECEI system, enabling the measurement of plasma waves in the GHz range in the form of modulated ECE signals and characterization of high-frequency turbulence during the evolution of pedestal. To achieve higher toroidal resolution in the turbulence measurement, the H-port ECEI system is now being upgraded to have a toroidally dual detector array of 2(toroidal) × 12(vertical) × 8(radial) channel configuration and a high-speed subsystem of 2(toroidal) × 4 channel configuration. The new mm-wave optics has been designed via beam propagation simulation, and the measured performance of the fabricated lens indicates a toroidal resolution of 8-10 cm depending on the focus position and zoom factor, allowing for the measurement of parallel wavenumber up to k‖ ∼ 0.8 cm-1.
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Affiliation(s)
- Dong-Kwon Kim
- Department of Physics, POSTECH, Pohang, Gyeongbuk 37673, Korea
- Korea Institute of Fusion Energy, Daejeon 34133, Korea
| | - Jaehyun Lee
- Korea Institute of Fusion Energy, Daejeon 34133, Korea
| | - Dong Jae Lee
- Korea Institute of Fusion Energy, Daejeon 34133, Korea
| | - Gunsu S Yun
- Department of Physics, POSTECH, Pohang, Gyeongbuk 37673, Korea
- Division of Advanced Nuclear Engineering, POSTECH, Pohang, Gyeongbuk 37673, Korea
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2
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Yu G, Zhu Y, Wang Y, Meneghini O, Smith SP, Zou Y, Luo C, Cao J, Tobias B, Diallo A, Kramer GJ, Ren Y, Luhmann NC. Integrated package of electron cyclotron emission imaging data processing and forward modeling in OMFIT. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:033540. [PMID: 33820069 DOI: 10.1063/5.0040448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 03/06/2021] [Indexed: 06/12/2023]
Abstract
An Electron Cyclotron Emission Imaging (ECEI) data analysis module has been developed for the OMFIT platform to accommodate the needs of users at the DIII-D tokamak for physics applications. The user can easily access the ECEI spatial observation windows in the plasma that are calculated based on the automatically retrieved hardware setup and available DIII-D equilibria, perform spectral analysis, and obtain 2D electron temperature fluctuation images. The module provides a powerful data post-processing package for extracting important physics parameters from the 2D measurements, including the radial structure and poloidal mode number of Alfven eigenmodes, as well as the frequency-vs-wavenumber dispersion relationship of broadband MHD. The module propagates characterized synthetic fluctuations for the user, so one can perform forward modeling tasks with simple analytical fluctuations.
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Affiliation(s)
- G Yu
- University of California, Davis, California 95616, USA
| | - Y Zhu
- University of California, Davis, California 95616, USA
| | - Y Wang
- University of California, Davis, California 95616, USA
| | - O Meneghini
- General Atomics, San Diego, California 92121, USA
| | - S P Smith
- General Atomics, San Diego, California 92121, USA
| | - Y Zou
- Southwestern Institute of Physics, Chengdu, Sichuan, 610041, China
| | - C Luo
- University of California, Davis, California 95616, USA
| | - J Cao
- University of California, Davis, California 95616, USA
| | - B Tobias
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - A Diallo
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08534, USA
| | - G J Kramer
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08534, USA
| | - Y Ren
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08534, USA
| | - N C Luhmann
- University of California, Davis, California 95616, USA
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3
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Sabot R, Giacalone JC, Nam Y, Berne A, Brun C, Elbèze D, Faisse F, Gargiulo L, Kim M, Lee W, Lotte P, Park HK, Santraine B, Yun G. Development of Microwave Imaging Diagnostics for WEST Tokamak. JOURNAL OF FUSION ENERGY 2019. [DOI: 10.1007/s10894-019-00216-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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4
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Sabot R, Nam Y, Brun C, Elbèze D, Faisse F, Gargiulo L, Kim M, Lee W, Lotte P, Park HK, Yun G. Integration of an Electron Cyclotron Imaging diagnostic system on the WEST tokamak. EPJ WEB OF CONFERENCES 2019. [DOI: 10.1051/epjconf/201920303011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
An Electron Cyclotron Emission Imaging (ECEI) diagnostic system for the WEST tokamak has been developed under the UNIST-WEST collaboration. This diagnostic system is designed to overcome accessibility and thermomechanical constraints for long pulse operation. The first O-mode channel will be installed in the first trimester of 2019 to probe the low field side (LFS) of the WEST plasma. Two large metallic reflective mirrors are installed inside the duct which is being used for maintenance access. They are suspended on a rail to facilitate mirror manipulation. The ex-vessel optical system (lens, detection array, etc.) is housed in a compact optical enclosure that fits in a tight free space between the port flange and tokamak access lobby. The design emphasized reproducibility of the precise alignment between in-vessel mirrors and optical enclosure since the both elements must be removed during shutdown period for maintenance access. The overall optical system was fully tested at UNIST last year. The test results demonstrated that the imaging optics can full access at any radial position on the LFS. The 2D beam pattern measurements were consistent with the design values.
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5
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Zhu Y, Ye Y, Yu JH, Tobias B, Pham AV, Wang Y, Luo C, Domier CW, Kramer G, Ren Y, Diallo A, Nazikian R, Chen M, Yu G, Luhmann NC. Liquid crystal polymer receiver modules for electron cyclotron emission imaging on the DIII-D tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:10H120. [PMID: 30399858 DOI: 10.1063/1.5035373] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 05/30/2018] [Indexed: 06/08/2023]
Abstract
A new generation of millimeter-wave heterodyne imaging receiver arrays has been developed and demonstrated on the DIII-D electron cyclotron emission imaging (ECEI) system. Improved circuit integration, improved noise performance, and enhanced shielding from out-of-band emission are made possible by using advanced liquid crystal polymer (LCP) substrates and monolithic microwave integrated circuit (MMIC) receiver chips. This array exhibits ∼15 dB additional gain and >30× reduction in noise temperature compared to previous generation ECEI arrays. Each LCP horn-waveguide module houses a 3 × 3 mm GaAs MMIC receiver chip, which consists of a low noise millimeter-wave preamplifier, balanced mixer, and IF amplifier together with a local oscillator multiplier chain driven at ∼12 GHz. A proof-of-principle partial LCP instrument with 5 poloidal channels was installed on DIII-D in 2017, with a full proof-of-principle system (20 poloidal × 8 radial channels) installed and commissioned in early 2018. The enhanced shielding of the LCP modules is seen to greatly reduce the sensitivity of ECEI signals to out-of-band microwave noise which has plagued previous ECEI studies on DIII-D. The LCP ECEI system is expected to be a valuable diagnostic tool for pedestal region measurements, focusing particularly on electron temperature evolution during edge localized mode bursting.
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Affiliation(s)
- Y Zhu
- University of California Davis, Davis, California 95616, USA
| | - Y Ye
- University of California Davis, Davis, California 95616, USA
| | - J-H Yu
- University of California Davis, Davis, California 95616, USA
| | - B Tobias
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - A-V Pham
- University of California Davis, Davis, California 95616, USA
| | - Y Wang
- University of California Davis, Davis, California 95616, USA
| | - C Luo
- University of California Davis, Davis, California 95616, USA
| | - C W Domier
- University of California Davis, Davis, California 95616, USA
| | - G Kramer
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - Y Ren
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - A Diallo
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - R Nazikian
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - M Chen
- University of California Davis, Davis, California 95616, USA
| | - G Yu
- University of California Davis, Davis, California 95616, USA
| | - N C Luhmann
- University of California Davis, Davis, California 95616, USA
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6
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Li JX, Zhu YL, Chen M, Cao JH, Dannenberg J, Domier C, Luhmann NC. A new method of out-of-focus millimeter wave imaging in fusion plasma diagnostics using Bessel beams. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:093506. [PMID: 30278691 DOI: 10.1063/1.5012778] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 08/26/2018] [Indexed: 06/08/2023]
Abstract
Electron cyclotron emission imaging (ECEI) and microwave imaging reflectometry diagnostics have been employed on a number of magnetic fusion plasma confinement devices. The common approach is based on a Gaussian beam assumption, which generates good spatial resolution (centimeter level). However, the radial focal depth is limited by the poloidal resolution, which is comparable with the Rayleigh length (∼150 mm). By contrast, a new Bessel beam approach has been developed and demonstrated to generate much longer focal depth with the property of propagation stability. To test the new approach, the DIII-D tokamak LCP ECEI optics have been re-designed to support a Bessel beam approach based on an axicon lens. The achievable radial coverage can exceed that of the current Gaussian approach by 3×. The imaging result is discussed in this paper based on the simulation analysis and laboratory testing result.
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Affiliation(s)
- J X Li
- State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Y L Zhu
- University of California at Davis, Davis, California 95616, USA
| | - M Chen
- University of California at Davis, Davis, California 95616, USA
| | - J H Cao
- University of California at Davis, Davis, California 95616, USA
| | - J Dannenberg
- University of California at Davis, Davis, California 95616, USA
| | - C Domier
- University of California at Davis, Davis, California 95616, USA
| | - N C Luhmann
- University of California at Davis, Davis, California 95616, USA
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7
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Lai J, Domier CW, Luhmann NC. Noise temperature improvement for magnetic fusion plasma millimeter wave imaging systems. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:033501. [PMID: 24689579 DOI: 10.1063/1.4866652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Significant progress has been made in the imaging and visualization of magnetohydrodynamic and microturbulence phenomena in magnetic fusion plasmas [B. Tobias et al., Plasma Fusion Res. 6, 2106042 (2011)]. Of particular importance have been microwave electron cyclotron emission imaging and microwave imaging reflectometry systems for imaging T(e) and n(e) fluctuations. These instruments have employed heterodyne receiver arrays with Schottky diode mixer elements directly connected to individual antennas. Consequently, the noise temperature has been strongly determined by the conversion loss with typical noise temperatures of ~60,000 K. However, this can be significantly improved by making use of recent advances in Monolithic Microwave Integrated Circuit chip low noise amplifiers to insert a pre-amplifier in front of the Schottky diode mixer element. In a proof-of-principle design at V-Band (50-75 GHz), significant improvement of noise temperature from the current 60,000 K to measured 4000 K has been obtained.
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Affiliation(s)
- J Lai
- Department of Electrical and Computer Engineering, University of California at Davis, Davis, California 95616, USA
| | - C W Domier
- Department of Electrical and Computer Engineering, University of California at Davis, Davis, California 95616, USA
| | - N C Luhmann
- Department of Electrical and Computer Engineering, University of California at Davis, Davis, California 95616, USA
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8
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Jiang M, Shi ZB, Che S, Domier CW, Luhmann NC, Hu X, Spear A, Liu ZT, Ding XT, Li J, Zhong WL, Chen W, Che YL, Fu BZ, Cui ZY, Sun P, Liu Y, Yang QW, Duan XR. Development of electron cyclotron emission imaging system on the HL-2A tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2013; 84:113501. [PMID: 24289395 DOI: 10.1063/1.4828671] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A 2D electron cyclotron emission imaging (ECEI) system has been developed for measurement of electron temperature fluctuations in the HL-2A tokamak. It is comprised of a front-end 24 channel heterodyne imaging array with a tunable RF range spanning 75-110 GHz, and a set of back-end ECEI electronics that together generate 24 × 8 = 192 channel images of the 2nd harmonic X-mode electron cyclotron emission from the HL-2A plasma. The simulated performance of the local oscillator (LO) optics and radio frequency (RF) optics is presented, together with the laboratory characterization results. The Gaussian beams from the LO optics are observed to properly cover the entire detector array. The ECE signals from the plasma are mixed with the LO signal in the array box, then delivered to the electronics system by low-loss microwave cables, and finally to the digitizers. The ECEI system can achieve temporal resolutions of ~μs, and spatial resolutions of 1 cm (radially) and 2 cm (poloidally).
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Affiliation(s)
- M Jiang
- Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041, China
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9
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Yun GS, Park HK, Lee W, Choi MJ, Choe GH, Park S, Bae YS, Lee KD, Yoon SW, Jeon YM, Domier CW, Luhmann NC, Tobias B, Donné AJH. Appearance and dynamics of helical flux tubes under electron cyclotron resonance heating in the core of KSTAR plasmas. PHYSICAL REVIEW LETTERS 2012; 109:145003. [PMID: 23083252 DOI: 10.1103/physrevlett.109.145003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Indexed: 06/01/2023]
Abstract
Dual (or sometimes multiple) flux tubes (DFTs) have been observed in the core of sawtoothing KSTAR tokamak plasmas with electron cyclotron resonance heating. The time evolution of the flux tubes visualized by a 2D electron cyclotron emission imaging diagnostic typically consists of four distinctive phases: (1) growth of one flux tube out of multiple small flux tubes during the initial buildup period following a sawtooth crash, resulting in a single dominant flux tube along the m/n=1/1 helical magnetic field lines, (2) sudden rapid growth of another flux tube via a fast heat transfer from the first one, resulting in approximately identical DFTs, (3) coalescence of the two flux tubes into a single m/n=1/1 flux tube resembling the internal kink mode in the normal sawteeth, which is explained by a model of two current-carrying wires confined on a flux surface, and (4) fast localized crash of the merged flux tube similar to the standard sawtooth crash. The dynamics of the DFTs implies that the internal kink mode is not a unique prerequisite to the sawtooth crash, providing a new insight on the control of the sawtooth.
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Affiliation(s)
- G S Yun
- POSTECH, Pohang 790-784, Korea.
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10
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Tobias BJ, Classen IGJ, Domier CW, Heidbrink WW, Luhmann NC, Nazikian R, Park HK, Spong DA, Van Zeeland MA. Fast ion induced shearing of 2D Alfvén eigenmodes measured by electron cyclotron emission imaging. PHYSICAL REVIEW LETTERS 2011; 106:075003. [PMID: 21405522 DOI: 10.1103/physrevlett.106.075003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Indexed: 05/30/2023]
Abstract
Two-dimensional images of electron temperature perturbations are obtained with electron cyclotron emission imaging (ECEI) on the DIII-D tokamak and compared to Alfvén eigenmode structures obtained by numerical modeling using both ideal MHD and hybrid MHD-gyrofluid codes. While many features of the observations are found to be in excellent agreement with simulations using an ideal MHD code (NOVA), other characteristics distinctly reveal the influence of fast ions on the mode structures. These features are found to be well described by the nonperturbative hybrid MHD-gyrofluid model TAEFL.
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Affiliation(s)
- B J Tobias
- University of California, Davis, 95616, USA
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11
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Classen IGJ, Boom JE, Suttrop W, Schmid E, Tobias B, Domier CW, Luhmann NC, Donné AJH, Jaspers RJE, de Vries PC, Park HK, Munsat T, García-Muñoz M, Schneider PA. 2D electron cyclotron emission imaging at ASDEX Upgrade (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D929. [PMID: 21033957 DOI: 10.1063/1.3483214] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The newly installed electron cyclotron emission imaging diagnostic on ASDEX Upgrade provides measurements of the 2D electron temperature dynamics with high spatial and temporal resolution. An overview of the technical and experimental properties of the system is presented. These properties are illustrated by the measurements of the edge localized mode and the reversed shear Alfvén eigenmode, showing both the advantage of having a two-dimensional (2D) measurement, as well as some of the limitations of electron cyclotron emission measurements. Furthermore, the application of singular value decomposition as a powerful tool for analyzing and filtering 2D data is presented.
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Affiliation(s)
- I G J Classen
- Max Planck Institut für Plasmaphysik, 85748 Garching, Germany.
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12
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Kong X, Domier CW, Luhmann NC. Antenna development for high field plasma imaging. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D923. [PMID: 21033955 DOI: 10.1063/1.3479117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Electron cyclotron emission imaging (ECEI) and microwave imaging reflectometry (MIR) are two microwave nonperturbing plasma visualization techniques that employ millimeter-wave imaging arrays with lens-coupled planar antennas, yielding time-resolved images of temperature (via ECEI) and electron density (via MIR) fluctuations within high temperature magnetic fusion plasmas. A series of new planar antennas have been developed that extend this technology to frequencies as high as 220 GHz for use on high field plasma devices with toroidal fields in excess of 3 T. Antenna designs are presented together with theoretical calculations, simulations, and experimental measurements.
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Affiliation(s)
- X Kong
- Department of Applied Science, University of California at Davis, Davis, California 95616, USA
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13
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Liang T, Tobias B, Kong X, Domier CW, Luhmann NC, Lee W, Yun GS, Park HK. Innovations in optical coupling of the KSTAR electron cyclotron emission imaging diagnostic. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D909. [PMID: 21033941 DOI: 10.1063/1.3478637] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The installation of a new electron cyclotron emission imaging diagnostic for the Korea Superconducting Tokamak Advanced Research (KSTAR) is underway, making use of a unique optical port cassette design, which allows placement of refractive elements inside the cryostat region without adverse effects. The result is unprecedented window access for the implementation of a state of the art imaging diagnostic. A dual-array optical design has been developed, capable of simultaneously imaging the high and low field sides of the plasma with independent features of focal plane translation, vertical zoom, and radial channel spacing. The number of translating optics has been minimized by making use of a zoom lens triplet and parabolic plasma facing lens for maximum channel uniformity over a continuous vertical zoom range of 3:1. The simulated performance of this design is presented along with preliminary laboratory characterization data.
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Affiliation(s)
- T Liang
- University of California at Davis, Davis, California 95616, USA.
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14
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Kim JB, Lee W, Yun GS, Park HK, Domier CW, Luhmann NC. Data acquisition and processing system of the electron cyclotron emission imaging system of the KSTAR tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D931. [PMID: 21033959 DOI: 10.1063/1.3479023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A new innovative electron cyclotron emission imaging (ECEI) diagnostic system for the Korean Superconducting Tokamak Advanced Research (KSTAR) produces a large amount of data. The design of the data acquisition and processing system of the ECEI diagnostic system should consider covering the large data production and flow. The system design is based on the layered structure scalable to the future extension to accommodate increasing data demands. Software architecture that allows a web-based monitoring of the operation status, remote experiment, and data analysis is discussed. The operating software will help machine operators and users validate the acquired data promptly, prepare next discharge, and enhance the experiment performance and data analysis in a distributed environment.
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Affiliation(s)
- J B Kim
- Department of Physics, POSTECH, San-31, Hyoja-dong, Nam-gu, Pohang, Kyungbuk 790-784, South Korea.
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15
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Tobias B, Domier CW, Liang T, Kong X, Yu L, Yun GS, Park HK, Classen IGJ, Boom JE, Donné AJH, Munsat T, Nazikian R, Van Zeeland M, Boivin RL, Luhmann NC. Commissioning of electron cyclotron emission imaging instrument on the DIII-D tokamak and first data. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D928. [PMID: 21033956 DOI: 10.1063/1.3460456] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A new electron cyclotron emission imaging diagnostic has been commissioned on the DIII-D tokamak. Dual detector arrays provide simultaneous two-dimensional images of T(e) fluctuations over radially distinct and reconfigurable regions, each with both vertical and radial zoom capability. A total of 320 (20 vertical×16 radial) channels are available. First data from this diagnostic demonstrate the acquisition of coherent electron temperature fluctuations as low as 0.1% with excellent clarity and spatial resolution. Details of the diagnostic features and capabilities are presented.
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Affiliation(s)
- B Tobias
- University of California at Davis, Davis, California 95616, USA.
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16
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Munsat T, Domier CW, Kong X, Liang T, Luhmann NC, Tobias BJ, Lee W, Park HK, Yun G, Classen IGJ, Donné AJH. Electron cyclotron emission imaging in tokamak plasmas. APPLIED OPTICS 2010; 49:E20-E30. [PMID: 20648116 DOI: 10.1364/ao.49.000e20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We discuss the recent history and latest developments of the electron cyclotron emission imaging diagnostic technique, wherein electron temperature is measured in magnetically confined plasmas with two-dimensional spatial resolution. The key enabling technologies for this technique are the large-aperture optical systems and the linear detector arrays sensitive to millimeter-wavelength radiation. We present the status and recent progress on existing instruments as well as new systems under development for future experiments. We also discuss data analysis techniques relevant to plasma imaging diagnostics and present recent temperature fluctuation results from the tokamak experiment for technology oriented research (TEXTOR).
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Affiliation(s)
- Tobin Munsat
- Department of Physics, University of Colorado, 390 UCB, Boulder, Colorado 80309, USA.
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